You would have to power sand to remove the white if you want a transparent. You can apply another solid stain over it in any color you like.

After stripper before brightener. Lightly sand. Use 60-80 grit.

When do I sand the deck, before or after the stripper & brightener?

The oxalic should not harem the stain but it also may not help the rust spots if the rust is under the stain. Do a test spot.

I have come to believe these are rust spots. We have been using an angle grinder to cut different old brackets and hardware, etc, during the redeckin...

Use the Restore A Deck Stripper/Brightener Kits.

That looks great! Love the two-toned look!

Could you post a picture please?

Thank you for the response. Do you have a recommendation on a product to use to prep the deck?

You will need to remove the Sikkens. Strip and sand for the prep. Stain with TWP 100 Series.